<!--
 * Tencent is pleased to support the open source community by making BK-JOB生物智算平台 available.
 *
 * Copyright (C) 2021 THL A29 Limited, a Tencent company.  All rights reserved.
 *
 * BK-JOB生物智算平台 is licensed under the MIT License.
 *
 * License for BK-JOB生物智算平台:
 *
 *
 * Terms of the MIT License:
 * ---------------------------------------------------
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
 * documentation files (the "Software"), to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and
 * to permit persons to whom the Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all copies or substantial portions of
 * the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT
 * THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
 * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
-->

<template>
  <icon v-if="showBack" class="jb-router-back" svg type="back1" @click="handleGoBack" />
</template>
<script>
import _ from 'lodash';

import {
  taskExport,
  taskImport,
} from '@utils/cache-helper';

export default {
  name: 'RouterBack',
  props: {
    /**
     * @desc 通过浏览器直接访问时总是显示路由回退按钮，通过iframe访问系统时需要根据场景显示路由回退按钮。
     */
    mode: {
      type: String,
      default: 'window',
    },
  },
  data() {
    return {
      showBack: false,
    };
  },
  watch: {
    '$route'() {
      this.check();
      const { name } = this.$route;
      // 路由变更清空作业导入缓存
      if (name !== 'taskImport') {
        taskImport.clearItem();
      }
      // 路由变更清空作业导入数据
      if (name !== 'taskExport') {
        taskExport.clearItem();
      }
    },
  },
  created() {
    this.timer = '';
    this.$once('hook:beforeDestroy', () => {
      clearTimeout(this.timer);
    });
  },
  mounted() {
    this.check();
  },
  methods: {
    check() {
      // iframe 嵌入的方式有两种场景
      // 1，paas 桌面的方式需要显示完整的导航
      // 2，第三方系统嵌入的方式不需要显示
      if (window.frames.length !== parent.frames.length
        && this.mode !== 'window') {
        // iframe 访问路由需要做定制处理
        this.showBack = false;
        // 在作业执行详情页面访问步骤执行详情页，显示路由回退按钮
        if (this.$route.name === 'historyStep'
          && this.$route.query.from === 'historyTask') {
          this.showBack = true;
        }
        return;
      }
      this.timer = setTimeout(() => {
        try {
          const viewInstance = _.last(this.$route.matched).instances.default || {};
          this.showBack = Object.prototype.hasOwnProperty.call(viewInstance, 'routerBack');
        } catch (error) {
          this.check();
        }
      }, 100);
    },
    handleGoBack() {
      window.routerFlashBack = true;
      const viewInstance = _.last(this.$route.matched).instances.default || {};
      if (typeof viewInstance.routerBack === 'function') {
        viewInstance.routerBack();
      }
    },
  },
};
</script>
<style lang='postcss' scoped>
.jb-router-back {
  position: relative;
  z-index: 1999;
  flex: 0 0 auto;
  padding: 16px 8px 16px 24px;
  margin-left: -24px;
  font-size: 14px;
  color: var(--color-primary);
  cursor: pointer;
}
</style>
